In Access 2013 I am trying to create a request for filling in the CPLL field:

update student T1 set T1.Sr_Bull = (Select AVG (Evaluation)
From performance T2 WHERE T2.IN_STUD = T1.in_stud)

But all the time this error:

in operation should be used
Updated subquery

Answer 1, Authority 100%

update AS T1 SET T1.SR_BALL = (
  SELECT AVG (estimate) from performance as t2 where t2.in_stud = t1.in_stud
)

Answer 2, Authority 100%

Try like this:

update student t1 set t1.cr_bull = avg (t2.activity)
From performance T2 WHERE T2.IN_STUD = T1.IN_STUD